CIA field agent Kelly Kaiser is drawn into a dangerous, top-secret mission to stop the number of people affected by the rowan tree's mysterious forces getting out of control.

Junior CIA field agent Kelly Kaiser jumps at the chance to lead a risky mission to enter Mexico and gather refugees from under the nose of the notorious drug lord who murdered her fiance.

When the mission takes a revenge-fuelled twist, Kelly finds herself facing dismissal, but Agnes Pendalon, the CIA's chief 'spook' lady, has other ideas. Kelly must lead a new, top-secret team to hunt down everyone infected by a magical, mysterious rowan tree's supernatural forces, and stop the outbreaks getting out of control. Facing an enemy she cannot see or define, Kelly is pulled into a war between alien forces and humanity, and soon discovers that there is more to her fiance's death than meets the eye . . .